Charles e



(No Model.)

0. E. SORIBNER. v TELEPHONE SWITCHBOARD APPARATUS.

No. 487,098. Patented Nov; 29, 1892.

- :INVENTOR Cfitzr es .Scrzhfiel' BY Mf ATTYS.

unnms Pn'zas co, PHQTOJJIHQ. WASHINGTON o c women STATES PATENT QFFICE;

CHARLES E. SCRIBNER, OF. CHICAGO, ILLINOIS, ASSIGNOR TO THE \VESTERNELECTRIC COMPANY, OF SAME PLACE.

TELEPHONE-SWITCHBOARD APPARATUS.

SPECIFICATION forming part of Letters Patent No. 487,098, dated November29, 1892.

Application filed April 21, 1892. Serial No. 430,] 52. (No model.)

T at whom it may concern.-

Be it known that I, CHARLES E. SCRIBNER,

a citizen of the United States, residing at Chicago, in the county ofCook and State of Illinois, have invented a certain new and usefulImprovement in Telephone-Switchboard Apparatus, (Case No. 307,) of whichthe following is a full, clear, concise, and exact description,reference being had to the accompanying drawing, forming a part of thisspecification.

My invention relates to the operators outfits for telephone-exchanges.Its object is to provide means for automatically disconnecting theoperators telephone set from a tele phone linecircuit.

My invention consists in a pivoted lever, retarded in its motion bysuitable means, provided with contact-points and circuit-connections,whereby it is adapted to connect the operators telephone with theconnecting-cord circuit when in one position, the switch orlever beingnormally held in such position by one of the connecting-plugs.

My invention is illustrated in the accompanying drawing. Therein I haveshown two sub-stations, each connected bya line-circuit withspring-jacks upon two sections of multiple-switchboard and with anindividual annunciator upon one of the boards, a pair ofconnecting-plugs of ordinary construction and their usual cord-circuit,and my improved automatic switch.

The apparatus at the substation-substation 1, for exampleis of the usualcharacter, comprising calling and signal-receiving apparatus, atelephone set, and a switch adapted to connect the signaling appliancesor the telephone set with the line-circuit, according to its position.The apparatus at the sub-station is connected in a grounded circuit bymeans of the line a with spring jack switches 12 1) upon two sections ccof multipleswitchboard at the exchange and with an individualannunciator d at the section 0 of switchboard. The individualannunciator d of the line to station 2 is placed upon the other section0 of switchboard, so as to be under the care of another attendingoperator.

The operators connecting apparatus com prises the connecting-plugs e c,which are connected together by flexible cords ff and a conductor g,callingkeys h h, each adapted to disconnect one of the plugs from theotherand to connect it with a grounded callinggenerator 'i, and thetelephone set It. A keyl 5-5- is provided, by which the operator isenabled to connect one terminal of her telephone set- 70 with theconductor g and thus with the circuit of two subscribers in connection.A clearing-out annunciator m is included in a branch between theconductor g and earth to respond to the signal fordisconnection. Thebell-crank lever n is pivoted at the point a. One arm n of the levercarries a flexible contact-spring n adapted to make contact with ananvil it, which is connected with the operators telephone set It.Aspiral spring 0 tends to withdraw the contact-spring n from its anvil11 The motion of the lever is re tarded by a piston 19, moving in adash-pot. The arm n of the lever is provided with a socket to receiveone of the connecting-plugs e, which normally rests therein, the Weightof the plug being sufficient to close the contactspring a upon the anviln in opposition to the tension of the spring 0. The lever 'n isconnected through the medium of the spring 0 with the conductor g. i

In the operation of the system shown a subscriber-for example, atstation 2-desiring 8o connection rotates his calling-generator, asusual, sending signaling-current through the line-circuit a and thedifferent spring-jacks b 5 through the annunciator d to earth, operatingthe annunciator and announcing the signal to the attendant at theswitchboard 0. The operator, seeing the signal, inserts theanswering-plug e of a pair of connectingplugs into the spring-jack b ather switchboard, whereby the circuit is extended from 0 station 2 overthe line a, to the line-spring q of the spring-jack b thence to the plug6, through the cord f, key 77., conductor 9 to the lever 71, thencethrough the contacts p 1? to the operators telephone set 70, thence toearth, and returning to station 2. The operator is thus enabled tocommunicate with the subscriber at station 2 and to receive his order,say, for connection with station 1. The

operator then proceeds to test the spring-jack [00 of line to station 1to determine whether the line is already in use or not in the usualmanner-tha.t,is,.by applying to, the test-ring q, of the spring j ack bat herbeardz the tip of the other connecting-plug e of the pair. If theline to station 1 were in use, the test-ring q would be connectedthrough the connecting-plug, by means of which connection. al-

ready existed with the line a, and thence to test-ring to which it wasapplied, thence over the line-circuit to earth, and at each suchapplication a click would be produced in the operators;telephone-receiver: which would indicate toherth-at the line was alreadyin use. WVhen the plug e was removed from. its socket in the lever 72 n,the lever at once be gan to rise in response; to the tension of thespring o; but being retarded in its movement by the pistonauddash-potpit would rise so slowly as to. allow the operatorsufficient time to makethe test with the plug 6 before separating the contacts 41, n anddisconnecting h-er telephone from the plug-circuit. Having found theline to station I not already in use, the. operatorinserts the plug e.fully intospring-jack-b, thereby completing a con tinuous loop circuit,including both thesnbstationsl and-2. The circnitmay be traced, asbefore, as far as the conductor g, whence his now extended through thekey h, cordf, and the plug e to the spring-jack b, then through theline-spring q thereof to the line a, and thence to sub-station 1. Theoperator now depresses the calling-key h, disconnecting the cordffromthe conductor 9 and connecting it with oneterminal of thecallinggenerator 2', whose other terminal is grounded, and thus sendinga call signal to station 1, to

which the signal-bell thereat responds.

If at any time the operator desires to connect her telephone set withthe circuit joining the two subscribers, she may do so by depressing thelistening-keyl. I V

When the subscribers have completed their conversation, one of them byrotating his callin g-gen eRLtQ 1-his telephoneswi'tchbeing in itslowest positioni s ends; a signal for disconnection over theline-circuit, which finds circuit to the conductor g, and thence throughthe clearing-out annunciator m to earth, operatingt e annn ci t r andindicati g o. the attending operator that the connection is no longerdesired.

I do not limit myself to the details of the construction herein shownand described, since numerous modifications of my invention will readilyoccur to those skilled in the art.

Having thus described my invention, I claimzasnewand desire to secure byLetters Patent 1. The combination, with a connecting plug, Of, a,switch-lever held in one position bytheplng. when out-of use,-switch-contacts thereon, and means for retarding the motion oftheswitch-lever, substantially asdescribed.

2. The combination, with a,.-(i0l1[l0.(3: lg" plug, of; switch-leverheld in. one position by the.- plugwhen, outof use,.switch-c ontactsthereon'adapted to be separatedwhenxsaid plug is remeved fo use, atelephone vse connected with one of said switclncontacts, the otherswitchcontact being connected with the plug-circuit, and meansforretardingthe motion of said switch-lever, substantially as specified.a v

3. The combination, with a connectingplug, of a switch-lever normallyheld in one positionby.the-weightof the, connecting-plug,

switch-contacts upon the said lever-adapted tobe separated when saidplugis, removed for use, circuit connections with said plug, a telephoneset; and other circuit. connections, whereby the telephone set is.normally connected through the switch-contacts with the plug-circuit,and means for retarding the said lever in its motion, substantially as,specified.

In witness whereof I hereunto subscribe my name this 5th day of April,A.D. 1892.

V CHARLES E. SCRIBNER. Witnesses:

F. R. MCBERTY, GEORGE L. ORAee.

